The actress Emma Thompson has spoken about her ongoing battle with depression, and how her work has saved her from "going under in a nasty way" during difficult times.

Speaking on Radio 4's Desert Island Discs, the Oscar-winning actress described being crippled throughout her life by the condition, which she first suffered while playing the leading role in a West End revival of the musical Me and My Girl in the 1980s.

She said: "I think my first bout of that was when I was doing Me and My Girl, funnily enough.

"I really didn't change my clothes or answer the phone, but went into the theatre every night and was cheerful and sang the Lambeth Walk.

"That's what actors do. But I think that was my first bout with an actual clinical depression."

During the programme, which is broadcast today, Kirsty Young, the presenter, asked Thompson about a five-year period during the 1990s, when she starred in seven films, was nominated for five Oscars and was also divorced from the actor and director, Kenneth Branagh.

Asked how she stayed sane, Thompson replied: "I don't think I did stay sane, actually. It was tough. I think I probably should have sought professional help long before I actually did, for all sorts of reasons.

"Yes, divorce, ghastly, painful business but also fame, in some ways a ghastly, painful business as well. You become slightly more public property in a way that's not necessarily always comfortable."

Thompson, 50, who is married to the actor Greg Wise, described how writing the screenplay for the film adaptation of Sense and Sensibility, in which she starred alongside Wise and Kate Winslet, helped her overcome another period of severe depression during the breakdown of her first marriage.

She said: "The only thing I could do was write. I used to crawl from the bedroom to the computer and just sit and write, and then I was alright, because I was not present.

"Sense and Sensibility really saved me from going under, I think, in a very nasty way."

The star of films including Nanny McPhee, Love Actually and An Education, also described acting as "an escape from myself, which I'm ashamed to say I enjoy very much."

Asked what she was escaping, Thompson said: "Oh, you know, the voices in my head. The constant "must do better", "must try harder" plus "you're too fat and not really a very good mother".

"That punitive conscience is part of my psychiatric problem."

Thompson also recounted how Wise initially pursued Winslet during the filming of Sense and Sensibility, because a soothsayer had told him that he would meet his future wife on the set.

She said: "Of course I was still married, so he thought it was Winslet and courted her assiduously.

"I remember him taking her to Glastonbury, which she hated because it was all hippyish, because Greg's quite hippyish and he kept thinking 'this just isn't working, I think she's just got to be wrong'."

The actress also attributed part of her success to the fact that her career is not based on her looks.

She said: "I don't think I am considered a beauty... I've always thought of myself as a character actress, so in a sense I've got much less to lose."

Thompson's choice of music for her desert island included Hold On by Tom Waits, Cantaloop (Flip Fantasia) by Us3 and Cándidos by Inti-Illimani.